Place the following steps in order related to an average star's life cycle: = The amount of fuel in the star becomes too low to continue to balance the pull of gravity, and the star's core begins to collapse.
= A supernova produces atoms more massive than iron and blows them into space, where they may become parts of new solar systems.
= The Big Bang occurred.
= The heat and friction from colliding hydrogen atoms initiates a nuclear reaction. The star is born
= The star will have a life that is determined by its mass.
= Gravity causes uneven masses of hydrogen to condense and swirl.
= The star grows to become a red giant as its core collapses, heats up, and fuses atoms up to the mass of iron